• Korean Journal of Weed Science
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• v.17 no.2
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• pp.199-206
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• 1997

Chlorsulfuron, an acetolactate-synthase-inhibiting sulfonylurea herbicide, induces many metabolic and physiological changes in susceptible plants. The objective of this study was to determine to what extent chlorsulfuton-induced phytotoxicity was due to a shortage of final products(the branched-chain amino acids valine, leucine, and isoleucine) or to an accumulation of a toxic metabolite(2-ketobutyrate), or both, in a susceptible species. Chlorsulfuron-treated canola seedlings showed growth inhibition and injury symptoms that included chlorosis, downward leaf rolling, and accumulation of anthocyanins. Supplementation with valine, leucine, and isoleucine prevented the chlorsulfuron-induced growth inhibition and injury symptoms only partially, suggesting that factor(s) other than a shortage of the branched-chain amino acids also are involved in the phytotoxicity. Canola seedlings treated with 2-ketobutyrate showed reduced growth, but they showed different changes in metabolites than seedlings treated with chlorsulfuron. The results suggest that 2-ketobutyrate is not involved in chlorsulfuron-induced phytotoxicity. We conclude that chlorsulfuron-induced phytotoxicity is due at least in part to a shortage of branched-chain amino acids.

• Korean Journal of Poultry Science
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• v.16 no.4
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• pp.219-232
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• 1989

The present study was done to investigate the mechanism of Pancreatic digestive enzyme secretion in response to dietary components in chicks. A simplefied pancreatic juice collection method, useful for a short-term experiment, was developed. By wing vein injection, it was shown that the increased trypsinogen and chymotrypsinogen, while neither other single amino acids nor glucose affected the secretion of enzymes, amylase, trypsinogen and chymotrypsinogen. Cholecystokinin (CCK) had an immediate effect on pancreatic enzyme secretion and this response was in a dose dependent fashion. The injection of CCK seemed to have selective stimulation favoring the secretion of chymotrypsinosen followed by amylase and trypsinogen. Simultaneous injection of single amino acid with CCK increased digestive enzyme secretion to various extents depending on the kind of amino acids whereas the injection of glucose with CCK did not affect when compared with that of CCK'alone. By varying doses, synergetic action of CCK plus amino acid on the secretion of pancreatic digestive enzymes was observed at 0.5mM for Val and 5mM for Arg. A further attempt was made to examine the effect of combined administration of amino acids with CCK on pancreatic enzyme secretion. The injected substances were an AAs mixture and combination of selected amino acids, i.e. Thr＋Phe＋Ile, Thr＋Phe. Thr＋Ile or Phe＋Ile. When increases in enzyme outputs for the first 30 min were compared , it was shown that the responses of three enzymes, amylase, trypsinogen and chymotrypsinogen, brought about by the administration of the AAs mixture was almost entirely accounted for by the combined injection of Thr＋Phe. Thus, it was well demonstrated that CCK and amino acids had a synergetic action on the secretion of a specific pancreatic digestive enzyme depending on a kind of amino acid injected.

• Food Science and Preservation
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• v.24 no.5
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• pp.697-706
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• 2017

The purpose of this study was to investigate the physiochemical properties of Doenjang was fermented by added with fungi and protease. The moisture content and pH of Doenjang added with protease (WP) were lower than those of control w/o protease while the contents of titratable acidity, reducing sugar, and amino-type nitrogen in WP were higher than control. The ${\alpha}$-amylase activities of Doenjang added with single and mixed Protease B were the highest at 4 weeks of fermentation period and protease activity of WP was about 4 times higher than that of control. The 4-9 kinds of free amino acids (proline, isoleucine, leucine, and phenylalanine etc.) in WP was increased in comparison with control. The DPPH radical scavenging activity and total polyphenol content were higher in WP than control. Total aerobic bacterial and fungal numbers were decreased depending on fermentation time regardless of addition of protease. In conclusion, the protease can be used as additives improving the quality and taste of fermented Doenjang.

• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.471-477
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• 1995

Extractive nitrogen, free amino acids, oligopeptides, nucleotides and related compounds, quaternary ammonium bases, and guanidino compounds were analyzed to evaluate quality of anchovy sauce. The commercial products contained low proximate composition, extractive nitrogen and other extractive components, than the experimentally prepared anchovy sauce. Both samples, commercial products and experimentally prepared anchovy sauce, were rich in free amino acids, such as glutamic acid, leucine, alanine, lysine, and aspartic acid. The extractive nitrogenous components which consist of total nucleotides and related compounds, total free amino acids, methionine, isoleucine, valine, taurine, tyrosine, histidine, leucine, aspartic acid, cystine, and lysine, showed significant correlation(p<0.01) with extractive nitrogen. Possibly, seven kinds of free amino acids such as methionine, isoleucine, valine, taurine, tyrosine, histidine, and leucine, might be recommend as quality indices of standardization for anchovy sauce.

• Journal of Embryo Transfer
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• v.13 no.3
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• pp.251-259
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• 1998

Concentrations of free amino acids in the BF of IVP bovine BL and HBL were examined in this study. The embryos derived from IVF oocytes were cultured in a SOFM containing BSA, EAA and NEAA. BF was aspirated from BL (180 h of age after insemination) and HBL (216 h of age after insemination), and introduced into drops of SOFM (30$\mu$l/drop) containing PVA through micromanipulation. The medium containing BF was then subjected to measurement of 20 amino acids by an automatic amino acid analyzer. The concentrations of isoleucine, leucine and methionine were higher (p〈0.05) in the BF from HBL than from BL, and no difference was found in aspartate or glutamate concentrations between BL and HBL, while threonine, alanine (p〈0.01) and the rest of the amino acids (p〈0.001) were significantly higher in the BF from HBL than from BL. Cystine was not found in either BL or HBL. A high concentration of glutamine was found in the BF from both BL and HBL, although it was not added to the culture medium. These results indicate that bovine BF contains several EAA (methionine in BL and isoleucine, leucine and methionine in HBL) and NEAA (alanine, glutamate, glycine, proline, serine and aspartate in BL, and glutamate and aspartate in HBL), and there is significant differences in the amino acid concentration in the BF between BL and HBL derived by WP.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.81-84
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• 2000

• Journal of Plant Biology
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• v.30 no.1
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• pp.1-9
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• 1987

Leaf mesophyll protoplasts of Nicotiana tabacum (nitrate reductase deficient mutant) were fused with cell suspension protoplasts of albino Petunia inflata in an electric field. Hybrid cell colonies were selected for nitrate reductase proficiency and chlorophyll synthesis. Five hybrid plant lines, regenerated from the selected calli lines, were analysed by electrophoresis, number of chromosomes and morphological characters. Somtic hybrid plants showed both parent patterns in the isozymesof isoleucine aminopeptidase and esterase. The hybrids had the expected chromosome number of 62 and exhibited an intermediate floral morphology when compared with the parents, but plant height and leaf arrangement were similar to N. tabacum.

• Journal of the Korean Data and Information Science Society
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• v.16 no.4
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• pp.745-758
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• 2005

This paper presents a statistical analysis on the position-specific distributions of amino acid residues in transmembrane proteins. A hidden Markov model segments membrane proteins to produce segmented regions of homogeneous statistical property from variable-length amino acids sequences. These segmented residues are analyzed by using chi-square statistic and relative-entropy in order to find position-specific amino acids. This analysis showed that isoleucine and valine concentrated on the center of membrane-spanning regions, tryptophan, tyrosine and positive residues were found frequently near both ends of membrane.

• The Microorganisms and Industry
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• v.20 no.2
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• pp.2-8
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• 1994

In this report, I will briefly explore the recent progresses in the metabolic engineering of Corynebacterium and related species, especially Corynebacterium glutamicum. I will focus mostly on the biosynthesis of aspartate family of amino acids, such as lysine and threonine. The information on the biosynthesis of other members of aspartate family of amino acids, such as methionine and isoleucine, is still very limited. Therefore, they will not be discussed here.

• Bulletin of the Korean Chemical Society
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• v.18 no.6
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• pp.648-653
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• 1997

Acetolactate synthase was purified from Escherichia coli MF2000/pTATX containing Arabidopsis thaliana acetolactate synthase gene. Purification steps included DEAE cellulose ion exchange column chromatography, phenyl sepharose hydrophobic column chromatography, hydroxylapatite affinity column chromatography, and Mono-Q HPLC. Molecular weight was estimated to be ∼65 KDa and purification fold was 109 times. The enzyme showed a pH optimum of 7 and the $K_M$ value was 5.9 mM. The purified enzyme was not inhibited by any of the end products, valine, leucine, and isoleucine.